In the centre of Takiwasi, traditional Amazonian curative practices are combined with modern psychotherapeutic techniques to treat drug-dependent people. This special form of therapy has not been studied scientifically. Therefore, an exploratory study has been conducted on the effects of individual therapeutic methods used in Takiwasi and how these effects have a long-term impact in the lives of former patients. In order to gain a more comprehensive understanding of the phenomena investigated, expert interviews, participating observations and field exposures were conducted on-site. The main interest, however, was to subjective patient views on their individual change process. Therefore, problem-centered interviews with six former patients were the core of the examination. The evaluation was carried out using the method of Grounded Theory. By creating a category scheme, the area of investigation was structured and a systematically ordered mapping of the most important phenomena was carried out. The author does not claim that this category scheme fully covers all phenomena of the development process. It allows statements about the content that respondents had insight and expressed. These statements cannot be generalized because of the lack of statistical protection. At this point, the most important findings of the investigation are summarized. • The decisive influence on the psyche of the patients is done by non-verbal manipulation of the body using plant medicine. • The plants result in a more comprehensive psychophysical cleaning, beyond physical detoxification. • The ritual techniques of Amazonian shamanism create a framework within which the Amazonian medicinal plants act as catalysts of autoexploration. Within the therapy contexts of the ayahuascaceremonies and diets, symbolic and concrete consciousness represents a decisive therapeutic factor. This fundamental effect of shamanic practices in Takiwasi is consistent with aspects of what shamans have done since early times. “Shamans are the original psychologist. They draw images from the unconscious to the surface. They bring what causes fear into consciousness so that people can handle it.” (Katz in Hoffmann, 1985, p. 248) • The intensive holistic experience was identified as a central effect of the plants. Connected to the consciousness processes, a deep perception of the related emotions occurs. • Within the ritual framework, the experience of the Transcendent is also made possible. Plants can open to people for the experience of a sense beyond the individual. • The results of the work confirm that the way in which psychoactive substances are dealing with has a decisive influence on the consequences that their use has for the individual and society (cf. Metzner, 1992). In Takiwasi, altered states of consciousness are induced for a therapeutic purpose. The personal importance of these experiences is evident from the extensive reference of interviewees to their experiences during the Ayahuascaceremonies. The associated relationship of these experiences with long-term changes in the life practice of respondents confirms the therapeutic value of changed states of consciousness. These are only considered as a source of healing in transpersonals psychology until now. (cf. Walsh & Vaughan, 1985) • Experiences and insights themselves are not sufficient for long-term change. The patient himself must play an active role in the therapeutic process. One step is to transfer the experienced to everyday life in Takivasi, the next to transfer the learned to everyday life after therapy. Your own action in life is essential for the longer term success of therapy. • Clear links between experiences in Takiwasi and long-term effects in life are visible. Experience in the context of plant-based therapy moments can thus be integrated into the personality and find a visible reflection in the life practice of respondents. • Change is a process, a process of work requires and implies acceptance of responsibility in life. • The total therapeutic intervention and the activity of the individual results in a holistic effect at best, which includes reconciliation with one's own history, fellow human beings, nature and transcendent. This study represents a first exploring step in a largely unexplored area. The findings of the study can serve as starting points for future research. In the following, individual phenomena can be examined in detail.